Inspecting the HIB_CTL register it seems that the HIB_CTL_CLK32EN is NOT asserted. This seemingly appears to happen randomly. Sometimes after a few power cycles, the module wakes up with the bit set as expected.

However, when the line called to assert the HIB_CTL_CLK32EN bit is carried out, the HIB_CTL_WRC is de-asserted. The main issue here is that the HibernateEnableExpClk(...) function then NEVER returns, as the _HibernateWriteComplete() seems to get the MCU stuck in an infinite loop (this function simply waits for the assertion of the HIB_CTL_WRC bit which never happens).

The "hib_stat_track" serves simply as a way for me to insert a breakpoint in the code. The "hibernation_status" retains a value of 0 throughout the execution.

I'm using the EK-TM4C123GXL to test it out on, with nothing but a USB cable connected. Can anyone tell me what I'm doing wrong? I think it's a power issue, but looking at the schematic for the board I cannot really figure out what the real problem appears to be.

It actually dawned upon me that VDD3ON was required about an hour after I made my post that this would be required since VBAT line is connected to VDD of the TM4C123G ... But thank you VERY much for confirming this, I'm ecasatic!

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